CR95HF writing to TAG-IT

Dear all,

I'm using a STM32 NUCLEO-L073 together with NUCLEO-NFC03A1.

and we want to read and write data to the tag RF37S113 Tag-it from TI.

This tag is compliance with ISO 15693.

I can successfully detect the TAG, but that's all. I can't write data to the tag.

I used the following seuqence:

>>.. represents data to CR95HF in hexadecimal

<<.. represents data from CR95HF in hexadecimal

ProtocolSelect

   >> 02 02 0109

   << 00 00

ISO15693_init

   >> 09 04  680101d1

   << 00 00

Inventory

   >> 04 03  26 01 00

   << 80 0d  00 00 7a 0f a1 66 e7 c0 07 e0  d389  00

   According to chapter 4.1 of iso 15693-3 MSB is 'e0', everything seems correct

Writing (01 02 03 04 into block 0) (UID is left, according to iso 15693 this is optional)

   >> 04 07  02 21 00 01 02 03 04

   << 80 05  01 03 04 24 00

   I got 5 bytes from TAG, according to standard I should only get 4 bytes in error or 3 bytes in ok case.

   I assume that 03 is the error code (according to standard (table 7): option code is not supported)

Reading

   >> 04 03  02 20 00

   << 80 08 00 00 00 00 00 77 cf 00

   As one see, data is not written.

What am I doing wrong?

I appreciate any hints or suggestions, thank you very much.

Best Regards

Stefan